The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A070291 a(n) = lcm(10,n)/gcd(10,n). 3
10, 5, 30, 10, 2, 15, 70, 20, 90, 1, 110, 30, 130, 35, 6, 40, 170, 45, 190, 2, 210, 55, 230, 60, 10, 65, 270, 70, 290, 3, 310, 80, 330, 85, 14, 90, 370, 95, 390, 4, 410, 105, 430, 110, 18, 115, 470, 120, 490, 5, 510, 130, 530, 135, 22, 140, 570, 145, 590, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,-1)
FORMULA
a(n) = A109051(n) / A109013(n). - R. J. Mathar, Feb 12 2019
a(n) = 2*a(n-10) - a(n-20). - R. J. Mathar, Feb 12 2019
Sum_{k=1..n} a(k) ~ (101/40)*n^2. - Amiram Eldar, Oct 07 2023
MATHEMATICA
Table[LCM[10, n]/GCD[10, n], {n, 80}] (* Harvey P. Dale, Nov 01 2013 *)
CROSSREFS
Sequence in context: A040093 A046797 A147675 * A361671 A183132 A141321
KEYWORD
easy,nonn
AUTHOR
Amarnath Murthy, May 10 2002
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 20 14:08 EDT 2024. Contains 372717 sequences. (Running on oeis4.)